A distortion calibration system generates a distortion map for a head-mounted display (HMD). The system includes a camera that takes pictures of a test pattern displayed by the HMD. The images are taken at different camera positions and/or states of the HMD. The system determines a distortion map using the captured images, and uploads it to the HMD as part of, e.g., an optical model. The HMD comprises an electronic display, an eye tracking unit, an optics block, and a module. The module estimates distortion values based on eye tracking information from the eye tracking unit, an optical model, and a state of the HMD (e., a distance between the optics block and the electronic display). The module determines an adjusted state of the HMD using the estimated distortion values, the eye tracking information, and the optical model, and adjusts the state of the HMD to the adjusted state.